Embodiments of the invention relate to vanes for use in a compressor. More particularly, embodiments of the invention relate to the shape of inlet guide vanes in an axial compressor.
Most axial compressors today have inlet guide vanes (IGVs) to modulate flow to the first stage, usually a first rotor stage, of the compressor. A variety of parameters define the shape and position of each IGV in a compressor. Among these parameters are the meanline of the IGV profile; the thickness distribution of the IGV profile; the lift coefficient, which is a multiplier of the meanline; and the stagger angle, which is the angle of the IGV relative to the axial direction of the compressor.
By varying the IGV parameters, multiple IGV profile and stagger angle combinations are possible for any given IGV exit condition, the IGV exit condition being the angle at which a gas, usually air, exits the IGV.
Examples of the invention include an inlet guide vane blade row for use in a compressor. The blade row has a plurality of inlet guide vanes. Each inlet guide vane has a meanline approximately equal to NACA standard A4K6 meanline, a thickness distribution approximately equal to NACA standard SR 63 thickness distribution, a stagger angle, and a lift coefficient between 0.0 and 0.8.
Other examples of the invention include a compressor. The compressor has a housing, a shaft, a compressor stage, and a plurality of inlet guide vanes attached to the housing. Each inlet guide vane has a meanline approximately equal to NACA standard A4K6 meanline, a thickness distribution approximately equal to NACA standard SR 63 thickness distribution, a stagger angle, and a lift coefficient between 0.0 and 0.8.
Other examples of the invention include methods of retrofitting a compressor with new inlet guide vanes, the compressor having existing inlet guide vanes and an existing inlet guide vane exit condition and the existing inlet guide vanes having an existing lift coefficient. The methods include designing the new inlet guide vanes such that the new inlet guide vanes have an exit condition substantially equal to the existing inlet guide vane exit condition, and the new inlet guide vanes have a new lift coefficient less than the existing lift coefficient. The methods further include removing the existing inlet guide vanes from the compressor; and installing the new inlet guide vanes in the compressor.